Monocyte chemoattractant protein

Function

Human synthetic monocyte chemoattractant protein 1 (MCP) belongs to the superfamily of chemokines, which are proteins involved in immunoregulatory and inflammatory processes. The gene for CCL2 is on chromosome 17 in region 17q11.2-q12. The superfamily can be subdivided into 4 smaller groups, depending on the N-ter arangment of the cysteines. The CCL2^[1] is also known as chemokine (C-C motif) ligand or: - MCP1 - small inducible cytokine A2 (SCYA2) - MCAF - GDCF-2 - SMC-CF - HSMCR30 - MGC9434 - GDCF-2 - HC11.

It exists as a monomer or a dimer, eventhough the homodimer form is preferred.

-> Binds to CCR2 and CCR4. Is tethered on endothelial cells by glycosaminoglycan (GAG) side chains of proteoglycans.

Ligands

K and PO4

Disease

CCL2 is implicated in several diseases like psoriasis and rheumatoid arthritis where the appear to recruit macrophages, therefore bolstering the inflammation on joints. It is thought to be involved in atherosclerosis in the recruitment of monocytes into the arterial wall. It has also been found elevated in the urine of people with lupus as a sign warning of inflammation of the kidney. CCL2 is overexpressed in epilepsy, brain ischemia, Alzheimer's disease, EAE and traumatic brain injury.

Structural highlights

CCL2 is part of the C-C motif group because of the covalent bond made between .^[2] Post translational modifications at the N-terminus can regulate receptor and target cell selectivity. Deletion of the N-terminal residue converts it from an activator of basophil to an eosinophil chemoattractant.